1. Field of the Invention
The present invention relates to light emission devices which include electron emission units, and, more particularly, to electron emission units having a plurality of electron emission devices which include patterned electron emitters.
2. Description of the Related Art
Light emission apparatuses typically include front substrates on which anode electrodes and phosphor layers are formed, and rear substrates on which electron emitters and driving electrodes are formed. Both edges of the front and rear substrates are integrally bonded via sealing members, and inner spaces thereof are exhausted, so that the front and rear substrates and the sealing members constitute vacuum containers.
The driving electrodes and cathode electrodes that are disposed parallel to the driving electrodes form gate electrodes. The electron emitters are typically disposed on side surfaces of the cathode electrodes facing the gate electrodes. The driving electrodes and the electron emitters form electron emission units.
Metal reflective layers may be disposed on one surface of the phosphor layers facing the rear substrates. The metal reflective layers reflect toward the front substrates visible light which is emitted from the phosphor layers in order to increase brightness. The anode electrodes, the phosphor layers, and the metal reflective layers form light emission units.
The light emission apparatuses apply a predetermined driving voltage to the cathode electrodes and the gate electrodes, and apply a direct current voltage (anode voltage) that is more than several thousands of volts to the anode electrodes. Electric fields are generated around the electron emitters by a voltage difference between the cathode electrodes and the gate electrodes. Electrons are discharged from the electric fields, and the electrons are drawn to the anode voltage and collide with the corresponding phosphor layers. The phosphor layers are then excited to emit visible light.
Conventional methods of forming electron emitters depend upon a specific shape of the electron emitters of a light emission apparatus. Therefore, a method of manufacturing the electron emitters is limited to the shape of the electron emitters, and thus the material for the electron emitters becomes limited.
Furthermore, the shape of conventional electron emitters has low manufacturing precision making it very difficult to manufacture a light emission apparatus having desired luminous efficiency.